It is well known that heating and cooling systems are employed for temperature control of buildings and various housing. Often fresh air will be ushered from outside of the building or house while exhaust air from within will be returned outdoors. Generally, a large amount of energy is expended in such cooling and heating systems. One way to conserve the cost for this expenditure of energy is by exchanging some of the heat and moisture between the air streams as they are entering and exiting the structure.
Accordingly such systems for exchanging the heat and humidity of the air streams have come to be known as energy recovery ventilation (ERV) systems. ERV involves the sensible and latent heat exchange of exhaust inside air with fresh outdoor air. The basis for such exchange is that the exhaust air flow and the intake airflow will possess different water vapor pressures and will furthermore be at different temperatures. For example, in summer if the intake airflow is warm and humid, energy is recovered by exchanging both the sensible heat and the latent heat with the cool and low humidity exhaust air. Alternatively, in winter, if the outdoor air is cold and dry, energy is recovered by exchanging both the dry cold air with the warmer, more humid exhaust air.
ERV systems are usually employed in conjunction with a heating and/or cooling system, and are made up of a device having an ERV core unit. The core unit is generally comprised of various stacked membranes separated by some type of barrier. The intake and exhaust air streams are transported to the core unit and made to pass by one another without intermixture on each side of the stacked plates.
Sensible heat exchange is generally simpler to accomplish since a thin layer barrier may transfer heat rather easily. On the other hand, latent heat transfer is affected by the change in humidity between the air streams. Accordingly, what is needed therefore is a system that allows for both the efficient exchange of both sensible and latent heat of the various intake and exhaust air flows.